1. Field of the Invention
The present invention relates to system status and error reporting. More specifically, the present invention relates to an improved method for implementing system status and error reporting in a device such as a serial buffer.
2. Related Art
System status and error reporting is typically performed by transmitting interrupts or messages from system devices to a system processor.
In interrupt-based schemes, an interrupt signal is transmitted from a system device to the system processor. Upon receiving this interrupt signal, the system processor software must poll the system devices one by one to determine which system device generated the interrupt to request service. As a result, the interrupt-based system will utilize significant processing power for polling, thereby increasing system processor utilization and degrading system performance.
In message-based schemes (or interrupt-based schemes that include an interrupt vector), the system processor may not need to poll the system devices to identify the system device that generated the message. However, the system processor software must poll the system device that generated the message to determine the system status or error being reported by this system device. In addition, each message generated by the system device is only able to inform the system processor of a single status or error. Thus, the system processor may not be informed of multiple status/errors at the same time. As a result, the message-based system will utilize significant processor power for context switch and interrupt handling, thereby increasing system processor utilization and degrading system performance.
The high latency and processor utilization exhibited by interrupt and message based schemes is especially detrimental in real time systems having embedded applications. It would therefore be desirable to have an improved status and error reporting scheme to minimize system processor utilization and reduce system interrupt latency.